The invention relates to a method of manufacturing an X-ray image intensifier tube having an entrance screen comprising a layer of luminescent material and a photocathode, which are provided together on a support, and to an X-ray image intensifier tube manufactured by means of this method.
Such a method is known from U.S. Pat. No. 3,821,763. An X-ray image intensifier tube is described therein having a luminescent layer preferably consisting of CsI, in which a structure is formed. On the one hand, a structure is formed in the layer of CsI described therein due to vapourdeposition parameters adapted to this end, such as the temperature of the substrate, the speed of vapour deposition and the like. On the other hand, as described in the aforementioned patent, an additional structure can be formed by a thermal treatment of the layer. A layer having such a structure is known as a layer having a crackled structure. X-ray image intensifier tubes provided with a layer of luminescent material having such a structure have proved satisfactory, but due to the increasingly higher requirements, especially with respect to the resolution of the tube, there is a need of optimizing the structure to this end. In practice, this means that a higher crack frequency in the layer is realized.